Valve structure adapted to be arranged in a flue bend



Nov. 7, 1967 L. A. A. CHAMBERT 3,

VALVE STRUCTURE ADAPTED TO BE ARRANGED I N A FLUE BEND Filed April 14,1964 dmdowfiml I L arsAxelAz-z ireas Chamberi: 32%

United States Patent 3,351,091 VALVE STRUCTURE ADAPTED TO BE ARRANGED INA FLUE BEND Lars Axel Andreas Chambert, Kallhall, Sweden, assigrlor toAktiebolaget Svenska Maskinverken, a Swedish jointstock company FiledApr. 14, 1964, Ser. No. 359,660 Claims priority, application Sweden,June 17, 1963,

6,680/63 3 Claims. (Cl. 137601) ABSTRACT OF THE DISCLOSURE A valvestructure consisting of a plurality of parallel straight vanes islocated in the bend of a duct to control flow through the duct;alternate vanes being mounted for rotation between open and closedpositions about axes that are parallel to and spaced inwardly of thelongitudinal edges of the rotatable vanes; the axes being so locatedwith respect to the cross sectional shape of the vanes and the crosssectional shape of the vanes being such that very little torque isrequired to effect their adjustment, and very little force is needed tohold them in any adjusted position.

This invention relates to a valve structure which is adapted to bearranged in a flue bend, for example in a fine of a heating boiler. Theinvention is characterized by one or more pivoted control means servingat the same time as guide vane means and as valve means, said pivotedcontrol means, in a plane parallel to the direction of flow, having sucha cross section shape that when said valve structure is fully open thefree cross sectional area of the flue is essentially constant in thedirection of flow, by which the flow losses are reduced as compared withflue bends without such a guide vane means, on one hand, and as comparedwith valves arranged in straight flues, on the other hand. In the fluethere may also be arranged one or more stationary control means.Preferably the control means are alternatingly arranged stationarily androtatably.

The pivoted control means may be so journaled and have such a crosssection that the torque produced by the flow and acting on each pivotedcontrol means is essentially balanced. This effect can be obtained inmany ways. Essential is, inter alia, the design of the front-viewed inthe direction of flow-edge of the pivoted control means. A constructionwhich gives such a balancing within the greater part of the controlrange, is characterized in that the pivoted control means are journaleddownstream of the largest cross sectional area of the flue bend, and inthat the control means are defined by a concave and a convex surface,the radius of curvature of the concave surface facing the inner surfaceof the flue bend being essentially twice as great as the radius ofcurvature of the other surface.

The invention is hereinafter described in detail with reference to theaccompanying drawing, which, by way of example, discloses a valveconstruction according to the invention.

The valve structure disclosed in the drawing is provided with fivecontrol means 1 to 5 serving at the same time as guide vane means andvalve means, and it is arranged in a flue bend between a horizontal flue6 of a heating boiler and a vertical flue 7 of said boiler. The controlmeans 1, 3 and 5 are rotatably mounted at 8, 9 and 10 respectively,whereas the means 2 and 4 are stationarily mounted. Due to the offset(downstream) journaling of the pivoted control means and due to the factthat said pivoted control means are defined substantially by a concaveand a convex surface with the radii of curvature a, and a/2respectively,

a balancing of the forces generated by the flow is achieved. The concavesurfaces facing the inner surface of the flue bend have thus twice asgreat a radius of curvature as the convex, outwardly facing surfaces. Inthe example shown all control means have, for the reasons ofmanufacture, been made equal, i.e. with the same radii of curvature aand a/2. Next to the front edge the radius of curvature of the convexsurface is less than a/2, which gives a still more improved balancing.In order to obtain the best possible flow conditions it may, however,sometimes be suit able to design the control means with radii increasingfrom the inner surface of the flue bend and outwards. On the stationarycontrol means 2 and 4 there are mounted stops or sealing rims 11 and 12.A similar stop 13 is mounted on the inner wall of the flue bend. Asindicated at the intermediate control means 3 in dash and dot lines,these stops 11 to 13 cooperate with the front part of the concavesurfaces of the movable control means. At the rearviewed in thedirection of fiowedge of the control means elongations 14 of the convexwalls of the control means 2 to 4 will contact each other when the valveis being completely shut. The elongation 14' on the control means 1 willthereby contact a stop or sealing rim 15 which is mounted on the outersurface of the flue bend. In the drawing there is finally shown in dashand dot lines how the control means may be stiffened by means of endplates 16.

The invention is not limited to the example described above but may bevaried within the scope of the appended claims. For example, theinvention is not adaptable only to flues of heating boilers. Essentialadvantages may, of course, also be gained if the construction accordingto the invention is used for example in coarse water conduits ofturbines or the like. Furthermore, the shape of the control means may bevaried to some extent from the 2:1 ratio of concave to convex surfaceradii mentioned above, without departing from the idea of the invention.Essential is only that the greater part of the cross section increaseobtained by the curvature of the flue is filled up with the controlmeans serving as guide plates as well as valves. A construction is alsopossible where this filling up is obtained to the greatest part only bythe stationary or only by the movable control means. The elements 11 to15 may either be arranged only to serve as stoppers or they may be sodesigned that they also provide for an effective sealing when the valveis being shut. Further modifications are, of course, also possiblewithin the frame of the invention.

What I claim is:

1. In combination with a duct along which fluid is adapted to flow,valve structure for controlling flow of fluid along said duct, saidvalve structure requiring substantially small forces for actuation toopen and closed positions and when in its open position producingnegligible resistance to flow of fluid along said duct, said valvestructure comprising:

(A) means defining an abrupt bend in the duct, substantially straightportions of the duct being upstream and downstream from said benddefining means and a portion of the bend defining means intermediate itsconnections with said substantially straight portions having a crosssection area greater than that of said upstream and downstream straightportions of the duct;

(B) a plurality of elongated vanes, each having a concave surface and agenerally opposite convex surface, the radius of curvature of saidconcave surface being on the order of twice that of the: convex surfaceso that each vane has substantial thickness, and said surfaces of eachvane being convergent towards parallel lengthwise extending leading andtrailing edges of the vane, the portion of the convex surface that isnear the leading edge of the vane having a substan- 3. The valvestructure of claim 1, further characterized tially smaller radius ofcurvature than the remainder by;

thereof; and said mounting means holding alternate vanes across the (C)means mounting said vanes in paced apart paralduct stationary andproviding for rotation of the relel relation in said bend defining meansand provid- 5 rnainder of the vanes.

ing for rotation of certain of the vanes about axes which are parallelto their leading and trailing edges References Cited and intermediatethem and which are located in said UNITED STATES PATENTS bend definingmeans, slightly downstream from the portion thereof of largest crosssectional area, said mounting means disposing the vanes, when the valvestructure is open, with their concave surfaces facing the bend and-theirleading edgesupstream relative-to FOREIGN PATENTS the direction of fluidflow through the-duct, and pro- 987,477 4/1951 Ffanceviding for rotationofsaid vanes toward their closed 15 positions in the direction todispose their convex sur- OTHER REFERENCES 1,872,599 8/1932 Grand 137601X 10 3,113,593 12/1963 Vicard 13839 faces upstream. Tuttle and Bailey:Air Control Devices for Air Condi- 2. The valve structure of claim 1,further characterized tioning, Heating and Ventilating. Catalog No. 41,pp. 50- by" 51, 7683, R4T7.

the radius of curvature of said surfaces of the several 20 vanes beingsuch that when the valve structure is in WILLIAM F. ODE PrimaryExamine'fl its fully open position the free cross section area at T A tt E said bend is substantially equal to that of theduct LAMBER' Sm anxammer' upstream and downstream therefrom.

1. IN COMBINATION WITH A DUCT ALONG WHICH FLUID IS ADAPTED TO FLOW,VALVE STRUCTURE FOR CONTROLLING FLOW OF FLUID ALONG SAID DUCT, SAIDVALVE STRUCTURE REQUIRING SUBSTANTIALLY SMALL FORCES FOR ACTUATION TOOPEN AND CLOSED POSITIONS AND WHEN IN ITS OPEN POSITION PRODUCINGNEGLIGIBLE RESISTANCE TO FLOW OF FLUID ALONG SAID DUCT, SAID VALVESTRUCTURE COMPRISING: (A) MEANS DEFINING AN ABRUPT BEND IN THE DUCT,SUBSTANTIALLY STRAIGHT PORTIONS OF THE DUCT BEING UPSTREAM ANDDOWNSTREAM FROM SAID BEND DEFINING MEANS AND A PORTION OF THE BENDDEFINING MEANS INTERMEDIATE ITS CONNECTIONS WITH SAID SUBSTANTIALLYSTRAIGHT PORTIONS HAVING A CROSS SECTION AREA GREATER THAN THAT OF SAIDUPSTREAM AND DOWNSTREAM STRAIGHT PORTIONS OF THE DUCT; (B) A PLURALITYOF ELONGATED VANES, EACH HAVING A CONCAVE SURFACE AND A GENERALLYOPPOSITE CONVEX SURFACE, THE RADIUS OF CURVATURE OF SAID CONCAVE SURFACEBEING ON THE ORDER OF TWICE THAT OF THE CONVEX SURFACE SO THAT EACH VANEHAS SUBSTANTIAL THICKNESS, AND SAID SURFACES OF EACH VANE BEINGCONVERGENT TOWARDS PARALLEL LENGTHWISE EXTENDING LEADING AND TRAILINGEDGES OF THE VANE, THE PORTION OF THE CONVEX SURFACE THAT IS NEAR THELEADING EDGE OF THE VANE HAVING A SUBSTANTIALLY SMALLER RADIUS OFCURVATURE THAN THE REMAINDER THEREOF; AND (C) MEANS MOUNTING SAID VANESIN SPACED APART PARALLEL RELATION IN SAID BEND DEFINING MEANS ANDPROVIDING FOR ROTATION OF CERTAIN OF THE VANES ABOUT AXES WHICH AREPARALLEL TO THEIR LEADING AND TRAILING EDGES AND INTERMEDIATE THEM ANDWHICH ARE LOCATED IN SAID BEND DEFINING MEANS SLIGHTLY DONWSTREAM FROMTHE PORTION THEREOF OF LARGEST CROSS SECTIONAL AREA, SAID MOUNTING MEANSDISPOSING THE VANES, WHEN THE VALVE STRUCTURE IS OPEN, WITH THEIRCONCAVE SURFACES FACING THE BEND AND THEIR LEADING EDGES UPSTREAMRELATIVE TO THE DIRECTION OF FLUID FLOW THROUGH THE DUCT, AND PROVIDINGFOR ROTATION OF SAID VANES TOWARD THEIR CLOSED POSITIONS IN THEDIRECTION TO DISPOSE THEIR CONVEX SURFACES UPSTREAM.